1. Field of the Invention
The invention relates to the field of electrical connections made in temporarily installed structures such as wiring for electrical power installed between office partition panels. In particular the invention concerns a wiring raceway for adapting vertical wall panels to be hardwired between electrical power outlets, rather than being connected by modular pre-wired conduit, plug connectors or the like.
2. Prior Art
Office partitions are very useful for subdividing an open floor space into work areas. The partitions provide privacy without the expense and permanence of structural walls, and are inexpensive and versatile as to the choice of particular configuration of panels used to enclose a particular work area. Typically the partitions comprise flat modular panels about 2-5 feet wide (0.6-1.5 m) and 3.5-5.5 feet high (1.1-1.7 m). Adjacent coplanar panels are attached edgewise, and panels also can be joined at right angle L or tee joints, forming a square or rectangular area of the desired floor area, for containing a desk or other worksurface.
Work areas usually require electrical service for operating equipment such as computers, calculators, lamps and so forth. Electrical power outlets or receptacles can be provided in the partition panels, for example along the lower edge of the panels, at an elevation slightly above a desktop, along vertical lines, etc. Any number of panels can be attached at any desired configuration of straight lengths, right angle or other angular bends, joints and the like, a typically varied arrangement being shown, for example, in U.S. Pat. No. 4,685,255--Kelley. Some provision must be made to attend to electrical connections between a source of electrical power and the electrical outlet receptacles (as well as other services such as installed lighting and the like).
Apart from electric power conductors, data transmission cables for computer networks and the like, telephone cables and other signalling wiring may be advantageously installed in and between partition panels. Whereas currents in power cables can induce currents in signalling wiring, it is advantageous either to shield between power and signalling wiring or to keep them well spaced from one another.
Electrical receptacles or mountings for electrical receptacles can by provided in an edge structure of the panels such as along a lower edge where the electrical receptacles as well as adjustable levelling legs are disposed. Typically, the electrical receptacles are mounted in enclosures such as standard receptacle boxes, connected to conduit through which wires must be fished. Alternatively flexible armored cable (e.g., BX cable) is used, with the armor being mechanically attached to the box and forming a sort of conduit. The electrical circuits are thus enclosed for safety.
According to one arrangement, the partition panel has two structural legs at the opposite lower corners, attached to an upwardly opening channel such that the channel is spaced from the panel. The channel defines the lowermost edge of the partition panel. Threaded leveling legs attach to the structural legs and/or to the lowermost edge channel. The area between the lowermost edge channel and the panel is used for routing conduits or modular wiring, and is covered by snap-on cover strips on both sides, for cosmetic purposes. Examples are disclosed in U.S. Pat. No. 5,381,994--Welch; U.S. Pat. No. 5,357,055--Sireci; U.S. Pat. No. 5,349,135--Mollenkopf et al.; U.S. Pat. No. 5,214,889--Nienhuis et al.; U.S. Pat. No. 5,209,035--Hodges et al.; and U.S. Pat. No. 4,135,755--Driscoll.
To employ pre-mounted receptacles or standard mounts for receptacles, electrical conductors are needed between the receptacles, which are wired in parallel, and to a circuit breaker panel. One known arrangement uses modular flexible cables of a length sufficient to reach from an electrical outlet in one panel to the electrical outlet in the next panel, or alternatively from an electrical outlet to the edge of the associated panel. End plugs terminate the cables and mate with the electrical outlets or with one another. The flexible cables can simply be stretched from one junction to the next, occupying the area at the bottom of the partition panel that is covered by the cover strip. Alternatively, flexible conduit can be run from connection to connection, around angles and the like, the conduit being mechanically attached at its ends to some point adjacent to the electrical connections.
According to some electrical building codes, for example in Chicago, modular connector cable arrangements for such partition panels are prohibited. All electrical outlets must be hardwired by licensed electricians. Also, where conduits are required or used, fitting and mechanically mounting the conduits is inconvenient and time consuming, and after placing the conduits the conductor wires must be fished endwise through each conduit length. What is needed is a modular panel arrangement that is better suited for hardwiring, and has features leading to convenience and speed of installation in a system of modular partition panels. What is also needed is a way in which the conventional partition panel arrangement of a panel on legs with a lowermost edge channel, can be modified optimally to suit the needs of hardwired partition systems.